Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 09 November
to 16:00 10 November 1996
The current alert level is ORANGE.

The level of activity at the volcano has increased during the past 24 hours with another swarm of shallow VT earthquakes occurring throughout the reporting period.

The VT swarm started at about 15:30 on 09 November. The activity was initially very low, with only two or three events per hour. Activity increased gradually during the night and peaked at about eight events per hour between 05:00 and 06:00. Activity has gradually declined since then and there were between three and five earthquakes per hour at the end of the reporting period. The level of activity in this swarm has not been as intense as during the swarms on 1-2 November and 4-6 November. All the VT earthquakes are located at shallow depths beneath the crater, similar to most of the activity in recent swarms. Four small long-period earthquakes were recorded overnight. No other types of seismic events were recorded. Seismic tremor was recorded on the Gages station between about 01:30 and 12:00 today. This type of signal has been associated with steam venting in the past. A flash flood signal occurred on the Gages station at 14:30 today.

The viewing conditions were very good first thing this morning when there was a moderate amount of steam emission. The upper parts of the volcano were shrouded in cloud for the rest of the day. One small rockfall was observed at 15:57, which travelled to the base of the debris fan.

EDM measurements were carried out today on the Whites to Castle Peak line. GPS measurements were made on the stations on the eastern side of the volcano. The data from both these have not yet been processed.

The average value of SO2 flux from the volcano measured using COSPEC was measured as about 240 tonnes per day. This is similar to levels measured over the last few days.

The continuing VT swarms are a cause for concern. There is a possibility of a rapid escalation of volcanic activity during the next few days. The volcano is in a very dangerous state and all residents should follow the recommendations laid out in the alert procedures and listen to Radio Montserrat.

Montserrat Volcano Observatory